1. Field of the Invention
The present invention relates generally to an imaging apparatus, and more particularly to a method for controlling a printhead for printing and maintaining a desired operating temperature of the printhead during printing.
2. Description of the Related Art
In today's thermal inkjet industry, achieving a desired printhead operating temperature before printing (pre-heat) is desirable in order to achieve acceptable print quality. The desired printhead operating temperature must then be maintained. The temperature may be maintained by using what is known as a substrate heater or by using the ink ejecting heaters to heat the chip by applying an electrical pulse which is not capable of ejecting ink, but is sufficient to heat the substrate at an acceptable rate to achieve operating temperature within an acceptable amount of time, referred to as non-nucleating heating (NNH). NNH heating is a beneficial method of heating for two main reasons: it does not require the additional silicon real estate that substrate heaters do, and it heats the silicon directly at the area of interest, the ink firing chamber (ink ejector).
However, a problem with using NNH heating to pre-heat the printhead is that the life of the heaters in the ink ejectors may be reduced, due to additional use and activity that a substrate heater would otherwise endure.